1. Field of the Invention
The invention is concerned with a method and an apparatus for lasting sides of shoes on lasts, comprising a side tack insertion device, wherein this device is moved along the lasting margin of the shoe on an operating path which follows the course of the shank region.
2. Prior Art
One side tack insertion device which moves along such an operating path is known from German patent specification No. 2316335. The operation of this device presupposes that, before the tacks are driven in, the lasting margin of the shoe on its last is already drawn tightly over the insole and held in this position.
In the case of a further side tack insertion device, known from German patent specification No. 3031649, the upper is tensioned over the last, before the tacks are inserted, by a wiper combined with the tack insertion device urging the lasting margin over the insole and thus pressing it against the insole, while at the same time a corresponding drafting force is applied to the upper. This leads to the upper being stretched on the last.
It has now become apparent that the stretching effected by such a wiper is insufficient, especially when it is a question of especially smooth leather. In such a case the wiper cannot effect a sufficient drafting force on the lasting margin, and this is especially disadvantageous if only a relatively small lasting margin is available.